Process for weighting silk.



PETEE. SCHMID AND KARL GROSS, 0F BASEL, SWITZERLAND; SAID GROSS ASSIGNOR T0 SAID SCHMID.

PROCESS FOR WEIGHTING SILK.

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No Drawing.

To all whom it may concern:

Be it known that we, PETER SoHMm, a citizen of the Swiss Republic, and KARL Gnoss, a subject of the King of Prussia, both residents of Basel, Switzerland, have invented new and useful Improvements in the Process for Weighting Silk, of which the following is a full, clear, and exact specification.

According to the various hitherto known processes for weighting silk the weighting of the silk is obtained by treating the silk alternately with suitable metal chlorid baths, such as tin chlorid baths and with alkali metal phosphate baths such as sodium phosphate baths and subsequently with an alkali metal silicate bath, such as a sodium silicate bath. Each treatment with a phosphate or a silicate bath lasts 45-60 minutes and, as very high weightings are usually desired, the process generally carried out shows three treatments with phosphate baths and one treatment with a silicate bath, so that the silk is exposed for 3 to 4 hours to the treatment at temperatures up to 65 C. We have now found that by weighting silk according to the said process an essential technical progress is attained, when the metal alkali phosphate baths and the alkali silicate bath are employed in form of froth or foam baths. The formation of froth or foam is obtained by adding to the phosphate or silicate bath a substance capable of acting as a froth producer in consequence of the saponification of its components by the alkali becoming free during the process. In this manner one prevents the bath from becoming too alkaline and consequently the metal (tin, etc.) previously applied to the silk fiber from being dissolved by the bath. Among the substances applicable to this purpose, are silku'orm-chrysalises, silkwastes containing chrysalises, such as bassinets, Italian gallettamini, French pelettes, sericin, water containing seriein, bone-dust, agar-agar, colophony or another resin and. the product resulting from the boiling of silkwormchrysalises or of silkwastes with water.

In order to carry out the improved process we can proceed as follows: Ungummed silk hanks having been treated in a tin chlorid bath and subsequently washed are suspended on removable and rotatable reels placed in the upper part of an open vessel Specification of Letters Patent.

Patented Dec. 1L2, llfi llb.

Application filed. ()ctober 7, 1915. Serial No. 54,497.

containing an alkali metal phosphate solution of about 6 to 7 Baum covering the bottom of the vessel for a depth of about 15 centimeters in such a manner that the silk is not submerged in the bath. In this vessel is placed a little bag containing 200 gr. silkworm-chrysalises for each 15 liters of the phosphate solution. In the said phosphate solution is immerged a steam coil which serves to heat the solution until it rises in the vessel along the hanks as a foam or froth enveloping at all parts of the same and this foam or froth is maintained applied to the silk for J; to 5 minutes or more. In course of the treatment of the silk with the said foam or froth of the phosphate solution, the reels are twice rotated slightly, in order to change the parts of the hanks in contact with the reels. After the steam supply to the steam coil has been cut off the foam or froth breaks down and the silk is washed and returned to the tin chlorid bath. The same treatment of the silk with th phosphate foam or froth is repeated after each of its treat- .ments with a tin chlorid bath. Thus the silk is subjected first to a treatment with a liquid bath of tin chlorid, then to a treatment with phosphate bath in form of froth or foam, again to a second treatment with a liquid bath of tin chlorid, then again to a second treatment with a phosphate bath 'in form of foam or froth and afterward to a third treatment with a liquid bath of tin chlorid and subsequently again to a third treatment with a phosphate bath in form of foam or froth. Finally it is treated with a silicate bath .of-eg B-aum in form of froth or foam, the said silicate bath containing 200' gr. silkworm-chrysalises for each 15 liters of the liquid silicate solution. In these treatments the silk would remain 1 minute in each of the three phosphate foam baths and 1 to 2 minutes in the silicate foam bath, amounting to 45 minutes for all the four baths, and is not subjected to any substantial moving during these treatments. On the contrary, according to the known weighting process the silk would remain (3 45) minutes in the phosphate baths and 60 minutes in the silicate bath, on the whole 195 minutes, and during these 195 minutes it would be'drawn to and fro and up and down or the liquid would be whipped through the silk. In consequence baths and alkali metal thereof the treatments with the foam baths yield goods which are less fiufi'y, more brilliant, more regular for the dyeing, more easily to be rereeled, besides resulting in large savings of Work, of apparatuses and of spaces. For a very large dyework an apparatus for the treatment with phosphate foam and an apparatus for the treatment with silicate foam will be suflicient. In a surprising manner the Weighting of the silk is also increased 10-15 per cent. The improved process also economizes phosphate and silicate, the quantity of liquid employed in the same being only 11; of the quantity of liquid necessary in the known process and the same bath can be used many times.

In the improved process the soap necessary to the formation of foam or froth is produced in the bath itself, the alkali of the phosphate or of the silicate being liberated during the process and saponifying the greases" of the silk-worm chrysalises, thus preventing the bath from becoming too alkaline and dissolving the tin from the silk fiber.

The little bag containing the chrysalises can be placed into the liquid phosphate or silicate solution or over the said liquid solution, provided that it is submerged in the foam bath in the course of the treatment.

An important advantage of the new process is that the temperature of foam bath remains invariable during the process, Without any intervention of the workman, While in'the known process the workman must take care to observe continually the required precise temperature of 65 C.

'A raw silk weighted according to the improved process and ungummed subsequently is as prefectly unguInmed and weighted as a silk ungummed in a first operation. A raw silk weighted according to the improved process with foam baths applied for a comparatively long time is as perfectly ungummed and weighted as a silk ungummed before or after the weighting.

Obviously it is possible to treat with froth phosphate baths with a treatment with a liquid silicate bath, or treatments withliquid phosphate baths with a treatment with a froth silicate bath.

The improved process can be employed for weighting silk in all forms, such as natural silk, schappe, silk tissues, silk ribbons, etc.

What We claim is:

1. In the process for weighting silk by treating it alternately with metal chlorid phosphate baths and subsequently with an alkali metal silicate bath, the saidmetal chlorid being the chlorid of a heavy metal and capable of being fixed upon the silk fiber by an alkali metal phosphate, the use of the alkali metal phosphate baths and of the alkali metal silicate bath in the form of froth or foam baths.

2. In the process for weighting silk by treating it alternately with metal chlorid baths and alkali metal phosphate baths and subsequently with an alkali metal silicate bath, the said metal chlorid being the chlorid of a heavy metal and capable of being fixed upon the silk fiber by an alkali metal phosphate, the use of the alkali metal phosphate baths in form of froth or foam baths.

3. In the process for weighting silk by treating it alternately with metal chlorid baths and alkali metal phosphate baths and subsequently with an alkali metal silicate bath, the said metal chlorid being the chlorid of a heavy metal and capable of being fixed upon the silk fiber by an alkali metal phosphate, the use of the alkali metal silicate bath in form of a froth or foam bath.

4. In the process for weighting silk by treating it alternately with metal chlorid baths and alkali metal phosphate baths and subsequently withan alkali metal silicate bath, the said metal chlorid being the chlorid of a heavy metal and capable of being fixed upon the silk fiber by an alkali metal phos phate, the use of the alkali metal phosphate baths and of the alkali metal silicate bath in the form of foam or froth baths produced by heating to ebullition the liquid baths conhaving components taining a substance which are saponifiable by the alkali becoming free during the process, in order to prevent the baths from becoming too alkaline and consequently the metal previously appliedto the silk fiber from being dissolved in the baths.

5. In the process-for weighting silk by treating it alternately with metal chlorid baths and alkali metal phosphate baths and subsequently with an alkali metal silicate bath, the said metal chlorid being the chlorid of a heavy'metal and capable of being fixed upon the silk fiber by an alkali metal phosphate, the use of the alkali metal phosphate baths in the form of foam or froth baths produced by heating to ebullition the liquid baths containing a substance having components which are saponifiable by the alkali becoming free during the process, in order to prevent the baths from be coming too alkaline and consequently the metal previously applied to the silk fiber from being dissolved in the baths.

6. In the process for weighting silk by treating it alternately with metal chlorid baths and alkali metal phosphate bath and subsequently with an alkali metal silicate bath, the said metal chlorid being the chlorid of being fixed upon the silk fiber by an alkali metal phosphate, the use of the alkali metal silicate bath in the form of a foam or froth bath produced by heating to ebullition theliquid bath containing a substance of a heavy metal and capable' having components which are saponifiable by the alkali becoming free during the process, in order to prevent the bath from becoming .too alkaline and consequently the metal previously applied to the silk fiber from being dissolved in the bath.

7. In the process for weighting silk by treating it alternately with metal chlorid baths and alkali metal phosphate baths and subsequently with an alkali metal silicate bath, the said metal chlorid being the chlorid of a heavy metal and capable of being fixed upon the sik fiber by an alkali metal phosphate, the use of the alkali metal phosphate baths and of the alkali metal silicate bath in the form of foam or froth baths produced by heating to ebullition the liquid baths containing silkworm chrysalises, in order to prevent the baths from becoming too alkaline and consequently the metal previously applied to the silk fiber from being dissolved in the baths.

8. In the process for weighting silk by treating it alternately with metal chlorid baths and alkali metal phosphate baths and subsequently with an alkali metal silicate bath, the said metal chlorid bein the chlorid of a heavy metal and capa le of being fixed upon the silk fiber by an alkali metal phosphate, the use of the alkali metal phosphate baths in the form of foam or froth baths produced by heating to ebullition the liquid baths containing silkwormchrysalises, in order to prevent the baths from becoming to alkaline, and consequently the metal previously applied to the silk fiber from being dissolved in the baths.

9. In the process for weighting silk by treating it alternately with metal qhlorid baths and alkali metal phosphate baths and subsequently with an alkali metal silicate bath, the said metal chlorid being the chlorid of aheavy metal and capable of being fixed upon the silk fiber by an alkali metal phosphate, the use of the alkali metal silicate bath in the form of a foam or froth bath produced by heating to ebullition the liquid bath containing silkworm-chrysalises, in order to prevent the bath from becoming too alkaline and consequently the metal previously applied to the silk fiber from being dissolved in the baths.

In witness whereof we have hereunto signed our names this 14th day of September, 1915, in the presence of two subscribing Witnesses.

PETER SGIIMID. KARL GROSS.

Witnesses ARNOLD ZUBER, Amman Rrrrna. 

